Hyperbaric
oxygenation during radiotherapy did not improve survival in patients with
advanced neoplastic disease.
Clinical Bottom Line:
1.
The addition of hyperbaric oxygen did not improve survival.
Appraised
by: Mike Bennett, Dept. of Diving and
Hyperbaric Medicine, Prince of Wales Hospital
Sydney; Saturday, 12 December,
1998
Clinical
Scenario: A patient with advanced
neoplastic disease suitable for radiation therapy.
Three-part
Question: In patients with advanced
neoplastic disease where radiotherapy is the indicated treatment, does
administration of hyperbaric oxygen at the time of irradiation, compared to
irradiation alone, result in any improvement in survival?
Search
Terms: Hyperbaric oxygenation,
radiotherapy.
The
Study:
Non-blinded randomised
controlled trial with intention-to-treat.
Advanced neoplastic disease
including head and neck (T3, T4, N1-3, Mo), cervix (IIIA, IIIB, IV), bladder (C,D),
recurrent rectal (Duke's C), oesophagus and brain. Radiotherapy prescribed.
Control group (N = 24; 24
analysed): 'Normal' 5 day, 1000 rad/week fractions to give total dose usual for
the particular tumour. Exact doses not given.
Experimental group (N = 25; 25
analysed): As above but each treatment given in hyperbaric conditions at 3ATA on
100% oxygen for about 50 minutes.
The
Evidence:
|
Outcome |
Time
to Outcome |
Radiation
Rate |
HBO
Rate |
Relative
risk reduction |
Absolute
risk reduction |
Numbers
needed |
|
Death |
1
year |
0.37 |
0.40 |
-4% |
-0.025 |
40 |
|
95%
CI: |
|
|
|
-48%
to 40% |
-0.30
to 0.25 |
NNH=3
to INF NNT=4 to
INF |
|
Survival |
2
years |
0.333 |
0.320 |
4% |
0.013 |
77 |
|
95%
CI: |
|
|
|
-75%
to 83% |
-0.25
to 0.28 |
NNT=4
to INF NNH=4 to
INF |
Comments:
1. Survival in individual tumour
groups did not differ between control and hyperbaric arms.
2. Study terminated prematurely
following an explosive decompression.
3. Power low, particularly for
individual tumour types.
4. It is not clear what dose of
oxygen or radiation each patient received.
Expiry date: January 2004
References:
1. Tobin DA, Vermund H. A
randomised study of hyperbaric oxygen as an adjunct to regularly fractionated
radiation therapy for clinical treatment of advanced neoplastic disease. Am J
Roentgenol Radium Ther Nucl Med. 1971; 3:613-621.
